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Date:

August 28, 2000

Subject:

Biotech-Papaya; Mobile DNA; Activist Watch; Need for

 

I read the post of Carol Gonsalves who opposed a moratorium on the
biotechnology debate. I agree with Ms. Gonsalves' post about the
moratorium.

If Ms. Gonsalves is on this list (or anyone else with the requested
information), I have a question about the virus-resistant transgenic
papaya developed at the Dennis Gonsalves laboratory at Cornell Univ.

Within the past two months I have twice received a messge on a list serve
(I do not think it was AgBioView) stating that the Hawaiian papaya growers
have shunned the virus-resistant transgenic papaya in droves after an
intitial wave of enthusiasm. The message gave two reasons: 1) lower
production of fruit per tree; 2) less profitability primarily because of
the Japanese market (i.e. the Japanese labeling laws, and Japanese
consumer concerns about genetically improved foods). Please comment on the
Hawaiian papaya situation and the status of the virus-resistant transgenic
papaya. I am interested in learning what is occurring. If anyone has
citations to reports about the situation, I would be happy to receive the
citations so that I may read the information myself.

Thanks in advance,

Drew

Drew L. Kershen
Earl Sneed Centennial Professor of Law
University of Oklahoma College of Law
=========================================

From: John McCarthy
Subj: Science & the Press

It's interesting that Anthony Shelton and some others identify Nature
and Science as both being "for profit". In fact Nature is published by the
commercial publisher MacMillan, and Science is published by the non-profit
American Association for the Advancement of Science and is the official
journal of AAAS. My dues to AAAS get me a subscription to Science. While
both Nature and Science have advertisements, you would have to ask to find
out how much of their income comes from ads and how much from dues or
subscriptions. Nature costs $169 per year.
=============================================

From: Roger Morton
Subject: Mobile DNA and Risk

The following is an excerpt from a recently published review from the
Plant Cell (Heslop-Harrison Plant Cell 2000 12 (5): p617- ). The paper is
interesting in the light of claims made by M-W. Ho from ISIS that we
should be very concerned about mutatgenic horizontally transferable DNA
sequences. As this review points out such sequences are found in all
plants already, in large numbers and are highly mutatagenic - for plants.
If such DNA is a risk then we will have to stop consuming plants for food.
Unfortunately such DNA elements are also in animals so we can't eat them
either. Well not if M-W.Ho is to be believed.

"As they insert themselves into the genome, retroelements act as mutagenic
agents" "Retroelements have been found in all plants investigated"
"Retroelements, typically including two or three open reading frames ...
and frequently represent half of the nuclear DNA"

Transposable Elements and Retroelements

Retroelements (class I transposable elements) are discrete components of
the plant nuclear genome that replicate and reinsert at multiple sites in
a complex process that involves activation of excision, DNA-dependent RNA
transcription, translation of the RNA into functional proteins,
RNA-dependent DNA synthesis (reverse transcription), and reintegration of
newly generated retroelement copies into the genome (reviewed in Kumar and
Bennetzen 1999). Major classes of retroelements include LINEs, SINEs,
copia- and gypsy-like elements, and retroviruses (Hull and Covey 1996 ;
Kumar 1998 ; Harper et al. 1999 ; Jakowitsch et al. 1999 ; Kumar and
Bennetzen 1999 ; Schmidt 1999). Retroelements, typically including two or
three open reading frames extending over 5 kb, tend to be highly amplified
and frequently represent half of the nuclear DNA (Pearce et al. 1996 ;
SanMiguel et al. 1996 ; Smit 1996 ).

Retroelements have been found in all plants investigated and are very
heterogeneous (Flavell et al. 1992 ), suggesting that they are an ancient
component of genomes. They are generally dispersed over plant chromosomes,
consistent with their mode of amplification, but may associate with
particular genomic regions. Most frequently, the rDNA and centromeric
regions, consisting of tandemly repeated DNA elements, show a lower
proportion of gypsy- and copia-like retroelements than do other regions
(Kamm et al. 1996 ; Heslop-Harrison et al. 1997 ; Kubis et al. 1998a ;
Schmidt 1999 ). It is hypothesized that retroelements are more abundant
around the centromeres of Arabidopsis chromosomes so as to limit the
disruption of genes (Fig 2; Brandes et al. 1997a). Relatively little is
known about the chromosomal organization of LINEs (Kubis et al. 1998b).

As they insert themselves into the genome, retroelements act as mutagenic
agents, thereby providing a putative source of biodiversity (Hirochika et
al. 1996 ; Heslop-Harrison et al. 1997 ; Ellis et al. 1998 ; Flavell et
al. 1998 ) and serving as markers of diversity. Regulatory mechanisms may
act to protect genomes from insertional mutagenesis (Lucas et al. 1995),
and it has been suggested that transgene-induced gene silencing reflects
mechanisms aiming to prevent genome invasion by retroelements. Plant
retrotransposon activity can be regulated at any step of the replication
cycle, including transcription, translation, reverse transcription,
nuclear import, and integration.

Along with DNA (class II) transposable elements and other elements such as
miniature inverted tandem elements (MITES; Wessler et al. 1995 ;
Casacuberta et al. 1998), insertion of retrotransposon elements can
inactivate or alter gene function (Wessler et al. 1995). Indeed,
transposition is estimated to account for 80% of the mutations detected in
Drosophila (Capy 1998). Transposons can excise, partially or completely
restoring gene function, and can also lead to chromosome rearrangements
such as inversions or translocations. Transposable elements can also act
to move elements such as exons and promoters into existing sequences so as
to create new gene functions and contribute to evolution (Plasterck 1998 ;
Moran et al. 1999). Indeed, retroelements are activated under stress
conditions (Wessler 1996 ; Grandbastien 1998 ; Kumar and Bennetzen 1999 ;
Walbot 1999 ). Alternative splicing of genes caused by transposable
elements has been shown in maize (Bureau and Wessler 1994a , Bureau and
Wessler 1994b ). Methylation of retroelements can also affect adjacent
sequences and lead to transcriptional repression (Yoder et al. 1997 ;
Goubely et al. 1999 ).


The sequences of degenerate and potentially active retroelements give
valuable data about genome evolution and phylogenetic relationships (Fig
4). In three species in the Vicia genus, copia retroelement copy number
varies from 1000 to 1,000,000, with more sequence heterogeneity being
present in species with higher copy number (Pearce et al. 1996). Although
in part due to random mutation of the high number of copies present in
most plant genomes, sequence variability is often nonuniformly distributed
along the retroelement: regulatory regions (including the long terminal
repeats of copia elements) can evolve faster than coding regions, perhaps
enabling elements to coexist with their host genomes without detriment
(Vernhettes et al. 1998 ). Although retroelement amplification leads to
large genomes (Bennetzen and Kellogg 1997)), it is probable that
retroelement turnover and loss can occur in a directed manner (Tatout et
al. 1998), leading to different retroelement compositions between species.
For example, chromosome sets in the cultivated hexaploid oat, Avena
sativa, can be discriminated by the presence of retroelement families
(Katsiotis et al. 1996 ).

--
Dr Roger Morton 02 6246 5069 (ph)
CSIRO Plant Industry 02 6246 5000 (fax)
=========================================
From: "Barry Hearn"

"Frankenstein' food
LYNNE LIN
The Straits Times

http://straitstimes.asia1.com.sg/world/wrld10_0829.html

The West may have the luxury of debating the use of genetically modified
food -- given its food abundancy. But for Asia, it's perhaps the only way
to save the continent's teeming hungry millions, says the head of research
at the International Rice Research Institute.
LYNNE LIN of The Straits Times Foreign Desk reports

has not been proven that genetically modified food poses a health
hazard to humans.

With food security not much of an issue in the West, the debate on
genetically modified food -- also known as ""Frankenstein'' food -- can
continue to rage, but for Asia, scientists and researchers are beginning
to conclude that it is perhaps the only way to end the continent's
starvation.

One such firm believer is Dr Gurdev Khush, principal plant breeder and
head of plant breeding, genetics and biochemistry at the Manila-based
International Rice Research Institute.

""Currently, close to 800 million people in the Asian region go to bed
hungry every night.

""With population growing at a rapid pace, food grain production must
increase by 50 per cent in the next 25 years to adequately feed the people
here.''

Genetically modified food is one answer.

""To attain food security, we need crop varieties with higher yields and
with more resistance to diseases and insects,'' he affirms.

Besides, increasing urbanisation is increasing demand for space for
factories, shopping complexes, housing and infrastructural projects.

In turn, this is eroding the total land available for cultivation.

Total yields are facing a further decline with plant diseases and insects
destroying 20-30 per cent of the total yield.

Why then is the West making a noise about genetic engineering? Dr Khush
believes it has to do with the abundancy of food grain in those markets.

""The vast majority of the scientific community does not see anything
wrong with genetically modified food...

Since there is no shortage of food in the US and Europe, critics question
the need.''

Brushing aside concerns raised by vocal groups about the potential risks
related to GM food consumption, Dr Khush explained: ""GM crops such as
maize, soybean and cotton have been widely grown for the last five
years... (yet) no harmful effects on human health or the environment have
been detected.

""Moreover, GM foods are thoroughly evaluated by regulatory agencies such
as the Environmental Protection Agency or the Food and Drug Administration
in the US.

""I do not see any problem with GM foods provided they are approved by the
regulatory agencies.''

In a future threatened by global warming, unpredictable climate changes
and the traditional enemies of agriculture -- locusts, pests, droughts,
floods and diseases -- diversity in technology becomes a strength and
necessity, not a luxury.

For Asia, he advocates the earliest introduction of genetically modified
rice.

""The poor rice consumers will be the greatest beneficiaries, as they
typically spend 50 to 60 per cent of their income on food. The new variety
will increase production and lower prices.''

Maybe then, the begging bowls will disappear.

----------------------------------------------
Barry Hearn EVAG Co-ordinator
Economically Viable Alternative Green; Bridging the gap between
environmental idealism and reality.
http://www.altgreen.com.au/ Have you fed a starving person today? Visit
http://www.thehungersite.com/ to have a sponsor donate food on your behalf
- costs you nothing.

===============================================
From: Andrew Apel
Sub: Activists Watch

Colleagues,

I'm sending you this information on the assumption that you are interested
in keeping up to date on what activists are up to. By now you may know
that Greenpeace USA, after massive resignations by its board of directors
and a 2/3 drop in membership, is merging with Ozone Action. The head of
Ozone action will after the merger become the head of Greenpeace USA.

The chairman of Ozone Action's board of directors started out with
Environmental Strategies, a project funded by the Tides Foundation, which
specializes in 'anonymizing' contributions and funneling them to activist
groups such as the Environmental Working Group (which targeted Stossel)
and Friends of the Earth.

I would also point out that Ozone Action has working ties with Fenton
Communications and the Environmental News Service (nominally the same
outfit).

Greenpeace also has more direct ties with Fenton Communications through
the CropChoice news network.

The upshot of all of this is that Greenpeace USA, since it is no longer of
independent financial means, has been drawn into the activist financial/PR
complex dominated by Fenton Communications and the Tides Foundation.

That being the case, one can reasonably project that Greenpeace USA
activities will (if the Ozone merger goes through) be more media-savvy
(because of Fenton) and better funded (through the Tides Foundation) than
during the last few years.
===================================================